You first need to select your timezone so that your system knows where it is
located. Look for your timezone in /usr/share/zoneinfo, then copy
it to /etc/localtime. Please avoid the
/usr/share/zoneinfo/Etc/GMT* timezones as their names do not
indicate the expected zones. For instance, GMT-8 is in fact GMT+8.

The core around which all distributions are built is the Linux kernel. It is the
layer between the user programs and your system hardware. Gentoo provides its
users several possible kernel sources. A full listing with description is
available at the Gentoo Kernel
Guide.

For ARM systems, the available kernels are vanilla-sources (the default
kernel source as distributed from kernel.org
and gentoo-sources (contains additional patches for performance and
stability).

Choose your kernel source and install it using emerge. The
USE="-doc" is necessary to avoid installing xorg-x11 or other
dependencies at this point. USE="symlink" is not necessary for a new
install, but ensures proper creation of the /usr/src/linux
symlink.

# USE="-doc symlink" emerge gentoo-sources

When you take a look in /usr/src you should see a symlink called
linux pointing to your kernel source. In this case, the installed
kernel source points to gentoo-sources-.
Your version may be different, so keep this in mind.

Manually configuring a kernel is often seen as the most difficult procedure a
Linux user ever has to perform. Nothing is less true -- after configuring a
couple of kernels you don't even remember that it was difficult ;)

However, one thing is true: you must know your system when you start
configuring a kernel manually. Most information can be gathered by emerging
pciutils (emerge pciutils) which contains lspci. You will now
be able to use lspci within the chrooted environment. You may safely
ignore any pcilib warnings (like pcilib: cannot open
/sys/bus/pci/devices) that lspci throws out. Alternatively, you can run
lspci from a non-chrooted environment. The results are the same.
You can also run lsmod to see what kernel modules the Installation CD
uses (it might provide you with a nice hint on what to enable).

Now go to your kernel source directory and execute make menuconfig. This
will fire up an ncurses-based configuration menu.

# cd /usr/src/linux
# make menuconfig

You will be greeted with several configuration sections. We'll first list some
options you must activate (otherwise Gentoo will not function, or not function
properly without additional tweaks).

Activating Required Options

Due to the highly specific nature of the embedded, we'll cover known
configurations for boards here. If your machine is not listed, then you should
visit the respective community website to figure out how to properly configure
your kernel.

Regardless of your machine, you should make sure to activate the use of
development and experimental code/drivers. You need this, otherwise some very
important code/drivers won't show up:

Please select your machine from the list below to jump to the configuration
section.

NetWinder

NetWinder configuration options

Remember that EXT2 support is required for the boot partition as that is the
only filesystem that the bootloader can read reliably. Otherwise, the only
filesystem that has been tested is EXT3 but your welcome to try your luck with
the others ;).

When you've finished configuring the kernel, continue with Compiling and Installing.

Compiling and Installing

Now that your kernel is configured, it is time to compile and install it. Exit
the configuration and start the compilation process:

# make && make modules_install

When the kernel has finished compiling, copy the kernel image to
/boot. Use whatever name you feel is appropriate for your kernel
choice and remember it as you will need it later on when you configure your
bootloader. Remember to replace with the
name and version of your kernel.

# cp vmlinux.gz /boot/

Now continue with Kernel Modules.

Kernel ModulesConfiguring the Modules

You should list the modules you want automatically loaded in
/etc/modules.autoload.d/kernel-2.6. You can add extra options to
the modules too if you want.

To view all available modules, run the following find command. Don't
forget to substitute with the version of
the kernel you just compiled:

# find /lib/modules// -type f -iname '*.o' -or -iname '*.ko'

For instance, to automatically load the 3c59x.o module, edit the
kernel-2.6 file and enter the module name in it.